Film developing apparatus



March 11, 1952 A. N. BROWN 2,588,696

FILM DEVELOPING APPARATUS Filed Dec. 8, 1947 INVENTOR. 440/74 /V. Eranx7 84 Y TORNEY.

Patented Mar. 11, 1952 UNITED STATES PATENT OFFICE FILM DEVELOPINGAPPARATUS Alpha N. Brown, Kansas City, Mo.

Application December 8, 1947, Serial No. 790,352

taining the correct temperature of the chemical solutions used. Inaddition, the length of time for development is an important factorsince this with the element of temperature, effects directly the colorrendition.

A third highly important consideration in the development of film liesin the agitation of such film within the solutions used throughout theprocess. In order, therefore, to approach absolutely perfectdevelopment, there should be maintained a time-temperature-agitationrelationship.

It is the most important object of this invention, therefore, to providefilm developing apparatus having means to maintain a predeterminedtemperature in the developing solutions used, structure permittingreduction in time of the entire developing process and means foragitating the film within the solution sufficiently during such process.

Another important object of this invention is the provision of filmdeveloping apparatus having means for quickly and easily directly thedeveloping solution into a tank wherein the film is disposed and at thesame time preventing the entrance of light into such tank as thesolution is being poured thereinto.

Another object of this invention is the pro vision of film developingapparatus having means for further speeding up the developing processthrough the medium of structure permitting extremely rapid removal ofthe solution from the developing tank and also, at the same time,preventing entrance of light into such tank while the solution is beingdrained therefrom.

A further object of this invention is the provision of film developingapparatus having a specially formed frame for the film to be developed,said frame having means thereon for detachable connection to manuallyoperable struc ture for agitating such frame and the film within thedeveloping tank.

A still further object of this invention is to provide film developingapparatus having a film supporting frame as above mentioned, said framebeing specially formed to give absolute protection to the film as thesame is being placed thereon and throughout the entire developingoperation which includes agitation within the developing tank.

Other objects of this invention include the provision of a speciallyformed and inexpensive bobbin for facilitating threading of the film onthe above mentioned frame; the way in which the aforesaid funnel isconstructed for detachable mounting upon the developing tank topositively prevent admission of light into the tank; the manner in whichthe film frame is detachably secured to the structure for agitating thesame within the developing tank; the way in which such detachable meansmay be utilized to support the film frame upon the developing tank; andthe manner in which the developing solution is maintained at apredetermined even temperature through the medium of a circumscribingtank adapted to contain a coolant.

Many additional minor objects will be made clear or become apparent asthe following specification progresses, reference being had to theaccompanying drawing, wherein:

Figure l is a side elevational view of film developing apparatus made inaccordance with my present invention, parts being broken away and insection to reveal details of construction.

Fig. 2 is a substantially central longitudinal cross sectional viewtaken on line 11-11 of Fig. 1.

Fig. 3 is a transverse cross sectional view taken on line IIIIII of Fig.1, looking in the direction of the arrows.

Fig. 4 is a detailed cross sectional view taken on line IV-IV of Fig. land Fig. 5 is a perspective view of the film threading bobbin per seshowing the same operably attached to said film.

In the drawing, an elongated, hollow, open top developing tank, broadlydesignated by the numeral [0, has a second outer tank I4 circumscribingsubstantially its entire length. This outermost tank It has a bottom 16provided with an opening 18 through which the developing tank ID passesand to which it is tightly secured as by welding.

The tank [0 is held in substantially central longitudinal alignment withthe tank l4 through the medium of a plurality of braces 28 disposed nearthe top of tank i4 and between the outer walls of tank I!) and theinnermost walls of tank M.

A funnel 22 designed to be supported by the tank ill at its uppermostend has an opening 24 within its bottom wall 26 that registers with arelatively short down-turned tube 28. Circumscribing this short tube 28and depending from the wall 26, is a longer tube 36 having a diametergreater than the diameter of the tube 28. This tube 30 slidablycircumscribes the uppermost end of the tank and rests upon an out-turnedflange 34 on the tank 10. The relatively short tube 28 depending fromthe opening 24 of the bottom wall 26 of funnel 22 has an outsidediameter less than the inside diameter of the tank 16 and istelescopically received by the latter.

It is thus clear that the members 28 and 35, together with the uppermostend of the tank l0, cooperate when the funnel 22 is in place topositively prevent any outside daylight from entering the developingtank l0 when the same is in use. During the process of developing of thefilm within the tank It], the relatively large open end 36 of the funnel22 permits quick and easy pouring of the developing solution into thetank 16 without danger of spilling or without undue loss of time. Inorder to prevent entrance of light into the tank l6 and yet permit thepouring of such liquid solutions into the funnel 22 and thence the tankH), a plurality of inclined overlapping baflles 3B are secured toopposed innermost faces of a section 3-1 of the funnel 22 as clearlyindicated in Fig. 2 of the drawings. This section 31 constitutes ahollow, open ended tubular member having a hooked-shape continuousflange 39 at its uppermost end that is looped over the uppermost edge'ofthe main section of funnel 22. Inclining of these baffles 38 permitsready flow ofthe solution downwardly through the funnel 22 and theoverlapping condition of such bafiies 38 positively prevents entrance oflight into the uppermost open end of the tank it.

A shaft 40 rotatably interconnecting opposed side walls of the funnel'22 has a manually operable crank 42 disposed exteriorly of funnel 22and an ofiset U-shaped portion 44 intermediate its ends. This U-shapedportion 44 receives a chain or the like 46, such chain 46 having one endthereof pivotally secured to the portion 44 of crank 46 at its bight.The chain 46 depends downwardly from the crank 40 through the hollowmember 28 of funnel 22 and thence into the tank ID.

The lowermost link of the chain 46 detachably receives a hook 48 formingapart of a supporting frame broadly designated by the numeral 56 forfilm 52 to be developed within thetank [6. This frame 56 comprises apair of spaced apart U-shaped members 54, each 'having one leg thereofreb-ent as at 56 to present a channel .53 for receiving the longitudinalmarginal edge of the strip of film 52.

The distance between the innermost ends of 'the channels 58 issubstantially the same as the width of the film 52, there beingsufficient clearance for permitting easy sliding of such film 52 intothe frame 56 which supports such film 52.

The opposed legs of the two elongated members 54 opposite to the rebentends 56, are interconnected by a plurality of relatively narrow crossbars 60 and the legs of members 54 having the channels 58 next adjacentthereto are connected by a number of members 62. These members 62 eachhave opposed legs 64 for forming a part thereof and inturned ears 66secured to the members 54 to one side of the legs of members 54 havingthe in-turned car 56 thereon. These legs 64 of the members 62 maintainsuch members 62 spaced from the film 52 'where the same will notinterfere in'any way when such film 52 is threaded "into the channels58. These members 62 are likewise relatively narrow and are spaced instaggered relationship with respect to the cross bars 60 to the end thatwhen the film is exposed to light, there will be no inter ference andsuch light will readily pass directly through such film 52. The formingof such members 60 and 62 relatively narrow will permit such light toreach the film 52 at an angle throughout its entire length.

A specially formed bobbin, clearly illustrated in Fig. 5, facilitatesthe threading of the film 52 within the frame 56. This bobbin consistsof an elongated relatively fiat plate 68 having a rib 10 formed thereonfor purposes of rigidity and a relatively sharp pointed prong 12extending laterally from one face thereof.

The width of the plate 68 is substantially the same as the distancebetween the channels 58 of the frame 56 and when the same is placed inuse, plate 68 is threaded into the channels 56, whereupon film 52 issecured to the sharp prong 12 by simply piercing the same as illustratedin Fig. 5.

A loop 14 mounted upon one end of the plate 66 opposite to the prong l2permits movement of this plate 56 longitudinally along the frame 56thereby threading film 52 thereon. When such threading is completed, theplate 68 is removed and the film 52 secured to the frameby hooking thesame over a prong 16. This prong 56 extends laterally from a plate 18secured to the members 54 of the frame 50 at the one end thereofadjacent the book 48. This hook 46'has one end thereof secured to theuppermost cross member 52 as at 86.

The outermost tank I4 is designed to contain a coolant to maintain thedeveloping solution within the tank ill at a predetermined temperatureand in the event such coolant includes ice and overflow is likely, apipe 82, secured to the outermost face of the tank 14 and registeringtherewith at its uppermost end accommodates such overflow.

A drain tube 64 communicating with the tank 14 at its lowermost end hasconnection with any suitable point of discharge, not shown. Thedeveloping tank in has an opening 86 formed in the lowermost end thereofthat communicates with a manually manipulable valve 88 of conventionalcharacter that in turn registers with a conduit 96. This conduit 96 maydischarge into any suitable container (not shown) A substantiallyU-shaped platform 92 overlies this opening 36 to the end that the liquidmay escape from the tank I6 when valve 88 is opened without permittingthe entrance of light into the tank IE).

A pair of U-shaped brackets 94 secured in any suitable manner to theoutermost face of the'tank l4, permits hooking of the entire assemblyover a suitable support thereby permitting quick and easy removal asdesired.

It is apparent from the foregoing that film developing apparatus hasbeen produced that is relatively inexpensive to manufacture and simpleto operate even for the most unskilled amateur.

The film 52 to be developed may be easily inserted in the frame 56through the use of the bobbin 58. After such film is thus positioned, itmay be secured in place by hooking the same over the out-turned spur 76.When the frame 59 and its contained film 52 is inserted within theuppermost open end of tank II], this frame 50, by its inherentconstruction, will prevent damage to the film 52 by holding it out-ofengaging relationship with the innermost-faces ofthe wallspf the tank I0. Until such time as the operator can move the funnel 22 in position,the hook 48 of frame 58 may be utilized by looping the same over theuppermost edge of the tank In holding the frame 50 and film 52 againstfalling downwardly within the tank 10.

The next step on the part of the operator is to hook the chain 46 overthe loop 48 and then positioning funnel 22 upon the tank l0. With thefilm 52 thus entirely enclosed against outside light, the operator mayquickly pour the developing solution into funnel 22 and immediatelycommence agitation of frame 50 and the film 52 by turning the crank 42.Solutions may be easily and quickly changed by opening the valve 88,such solution within tank flowing rapidly by gravity into the hose 90.Closing of the valve 48 and pouring other chemicals into the funnel 22makes the apparatus ready for the next step of the developing process.When the film 52 is to be removed from the tank It for exposing the sameto light, it is not necessary for the operator to leave any fingerprints or other damaging marks on the film 52 or emulsion thereon sincehe may easily grasp the members 54 of frame 50. In all respectstherefore, it is easily seen that the time element, the necessaryagitation of the film 52 and the maintenance of the chemicals within thetank [0 at a predetermined temperature, have all been adequatelyaccomplished through the use of the device above described.

Manifestly, many changes and modifications may be made particularly withrespect to details of construction without departing from the broadprinciples herein contemplated and it is, therefore, desired to belimited only by the spirit of this invention as defined by the appendedclaims.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

A holder for roll film comprising a pair of 0 identical, elongatedmembers, each member being U-shaped in cross-section, presenting a pairof legs; a plurality of cross bars on one side of the members andjoining proximal legs of the opposite U-shaped members for holding themembers 6 in spaced opposed parallelism; a plurality of U- shapedelements on the other and opposite side of the members and joining theopposite legs thereof, said elements being offset along the membarsrelative to the cross bars, said'opposite legs having portions outwardlyrebent with respect to the elongated member and opposite each otherthereby presenting a pair of opposed V-shaped channels coextensive inlength with the members,

10 the distance between the apexes of the channels being substantiallythe same as the width of a film to be held thereby whereby the latter isfrictionally gripped along the marginal edges thereof, the bights ofsaid elements being spaced outwardly from said channels; a plate carriedby the members at one end thereof having a film-receiving prong thereon;and a hook on one of said U-shaped elements adjacent said one end of themembers for supporting the holder and the film carried thereby.

ALPHA N. BROWN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 897,251 Graves Aug. 25, 1908 391,237,657 Kroedel Aug. 21, 1917 1,245,848 Winslow Nov. 6, 1917 1,429,270Barber Sept. 19, 1922 1,845,800 Kreuder Feb. 16, 1932 2,112,605 PlessMar. 29, 1938 2,325,120 Forse July 27, 1943 2,341,666 Spota Feb. 15,1944 2,344,998 Morgan et al Mar. 28, 1944 2,349,028 Wildman May 16, 19442,452,389 OClair .c Oct. 26, 1948 40 FOREIGN PATENTS Number Country Date1,885 France Aug. 31, 1903 (2nd addition to No. 269,637) 5 19,164 GreatBritain of 1904 527,944 France Aug. 5, 1921

